Usmanov's trial began in September at the Tashkent city court. Human rights campaigners have claimed the defendant and witnesses for the prosecution were physically abused.
Usmanov's father, Ulugbek, told RFE/RL's Uzbek Service that his son denies the charges and will appeal the sentence.
"None of the charges brought against my son have been supported with evidence," he said. "Additionally, four witnesses for the prosecution were summoned to appear before the court. All four publicly stated that they had been tortured and forced to sign statements accusing my son."
Surat Ikramov of the Initiative Group of Human Rights Defenders says in a statement the court refused to investigate allegations of torture. He also says no witness for the defense was allowed in the courtroom.
Usmanov was sentenced to 10 years in jail in 2001 on charges of threatening Uzbekistan's constitutional order, then granted his freedom under an amnesty.